Vanderbilt University has established a state-of-the-art microarray facility that is presently supported by the Vanderbilt-Ingram Cancer Center, the Diabetes Center and the Vanderbilt NIDDK Biotechnology Center. This facility provides high quality microarray production, hybridization and data analysis for members of these research centers. Core B will enable Program investigators access to the full spectrum of advanced technologies offered by this resource. Projects 0010, 0011 and 0013 will utilize Core B for proposed experiments aimed at revealing changes in gene expression associated with arrhythmia susceptibility. In Project 0010, experiments have been outlined to compare gene expression patterns between mice expressing a CaM Kinase II inhibitory peptide or control peptide in heart in experimental cardiomyopathies. These experiments seek knowledge of the role of CaMKII and its upstream and downstream regulators on molecular pathways leading to cardiac failure and arrhythmias. Project 0011 will utilize microarray experiments to study an in vitro cell culture system for examining electrical remodeling in atrial myocytes subjected to rapid pacing, with the goal of identifying early molecular changes contributing to an atrial fibrillation-susceptible phenotype. Project 0013 has developed a novel molecular resource, a canine expressed sequence tag (EST) collection from heart, that will be used to develop gene arrays to be applied initially to dog models of susceptibility to arrhythmias closely resembling human disease. Core B consists of two main critical elements: (1) microarray production and hybridization; and (2) data acquisition and analysis. Both elements operate with state-of-the-art technological and computational tools that guarantee superior quality and reliability in microarray experiments. The Core will support the salaries of key personnel needed for operating the core, equipment and other infrastructure costs that enable expansion of existing services, and support for expertise in analysis of the data that emerge from microarray experiments.